Method and apparatus for drying rubber



May 25,1925.

w. T. RUNA LS, JR METHOD AND APPARATUS FOR DRYING RUBBER" Filed Feb. 25, 1920 3 Shee May 25,1926. 1,585,739 I W. T. RUNALS, JR

METHOD AND APPARATUS FOR DRYING RUBBER F'il b. 25 l 3 Sheets-Sheet 2 w. T. RUNALS, JR

METHOD AND APPARATUS FOR DRYING RUBBER d Feb- 25, 1920 3 Sheets-Sheet 3 5' b jx? w i m, I V r"! 1" 1 1 F 11 11 151' mi l I I l 77 w'@%7 k/r Patented May 25, 1926.

UNITED STATES WILLIAM '1. RUNALS, JR, 013 AKRON, OHIO, ASSIGNOR TO THE FIRESTONE TIRE AND RUBBER COMPANY, OF AKRON, OHIO, A CORPORATION OFOHIO. I

mnmnon AND arrAnA'rUs FOB DRYING RUBBER.

Application filed February 25, 1920. Serial No. 361,808.

This invention relates to an improved method of drying sheet rubber by which it is more rapidly and efliciently dried, and danger of burning the rubber is avoided.

-By the method herein described, it is possible to control the action of the dr mg agent and prevent injury to the ru ber whileobtaining the maximum efiiciency for the apparatus;

The apparatus is designed to hold a large amount of the rubber in sheet form and to insure the complete saturation of the drying agent, the gas used, whether air or some other medium being circulated around the rubber until it carries its full load of moisture, a certain percentage of the gas being cations are included within the'scope of the invention.

In the drawings:

Fig. 1 is a longitudinal section through the drying apparatus.

Fig. 2 is a plan view.

Fig. 3 is a cross section.

In the apparatus are contained any,number of chambers, one being shown, which comprises enclosing walls 1, a top 2, and a floor 3. In the floor at a number of places are set a plurality of gratings or other vents 4, which connect the interior of the drying chamber with a room 10 underneath'the floor.

In the upper part of the chamber is arranged a pipe or flue 5 by means of which the drying medium is introduced into the chamber, through a plurality of branch pipes 6, which may be dampered at 6 if desired. The drying medium which is introduced into the chamber may be forced in by fans and is heated to the proper temperature.

In the floor of the drying chamber are If the air or othermedium is alset a plurality of vents or outlets 7 which lead to a main exhaust pipe 8 connected with a fan 9 which draws out the air or other gas from the chamber. 1

From the room 10 at the bottom of th apparatus lead a plurality of ducts or bypasses 11, which terminate in downwardly directed discharge passages in which are located blowers or fans 12 driven b motors 13, so that a constant circulation is maintained through the drying chamber, room 10 and flues 11. At any convenient point in the by-passes, shown here at the entrance into the chamber, are, arranged heatmg means, preferably coils of pipe 14, through which steam or some other agent may be circulated. Bycontrol of the temperature of the heating means 14, the air in the drying chamber may be maintained at a constant temperature, and this regulation may be carried on in any suitable'way.

The'rubber, in sheet form, which has been.

washed and is ready for/ drying, is indicated at 15 and is hungover a plurality of horizontal arms 16 supported by skids 17. The skids are introduced into the chamber through the door 18. The warm air, or

other drying medium, is maintained in constant circulation by the fan 12 and is reheated as it passes over heating coils 14:, by

which means the temperature of the air is maintained uniform, and the drop in tem perature due to the absorption of moisture is compensated for. By constantly circulating the gas through the chamber, it may be forced to take up its full complement of moisture until it reaches the saturation point. By th s means the maximum efliciency may be obtalned from the gas. A supply of fresh gas may be introduced through the 5 pipe 5, enough being added so that the gas is maintained at a little below its saturation point, and the excess air is withdrawn through the pipe 8. The gas may be withdrawn and replenished constantly, or intermittently, as may be found desirable.

It is within the scope of this invention to use other drying mediums than air and it will be found that superior results are obtained. As an example of other mediums, use may be made of flue-gas which is inert and will not afiect the rubber. Other inert gases may be employed, and I am not limited to that mentioned. The gases which are inert may be raised to a much higher temperature than air and will not inj ure the rubber. The higher the temperature of the gas, the greater will be its power of absorbing moisture, and no injury will be done to the rubber, as the burning of the rubber is-due to oxidation which cannot take place in the inert gas. V

By the use of the apparatus and method described superior results are obtained in the drying of the rubber and greater economy is accomplished.

It is possible to realize the advantages and benefits of this invention while departing from the specific embodiment shown, and I do not intend to be limited to such details, and anything found within the scope of the claims and not departing from the spirit of this invention is intended to be covered hereby.

I claim:

1. In the art of drying rubber,the steps of supporting the rubber in an enclosed chamber with a heated gaseous drying medium, allowing the medium to reach a substan tially saturated condition from the moisture contained in the rubber, rapidly circulating the medium by withdrawing it from the chamber and returning it again, re-heating the medium to replace the heat lost by evaporation of the moisture in the rubber and removing from the body of the substantially saturated inedium a portion thereof and replacing the portion withdrawn by a fresh supply.

2. In the art of drying rubber, subjecting the rubber to the action of a rapidly circulating drying medium, which is maintained at'a constant high temperature and a constant state of substantial saturation, by reheating the medium during the entire operation to replace the heat lost by evaporation and withdrawning a portion of the medium as it reaches the saturation point and replacing the medium withdrawn by a fresh supply thereof.

3. In the art of drying rubber, subjecting the rubber to the action of a drying medium, by circulating the medium at a ra id rate and in large volume about the rub er and maintaining it at a constant high temperature and a constant state of substantial saturation from the moisture in the rubber, by reheating the medium during the entire operation to replace the heat lost by evaporation and withdrawing a portion of the medium as it reaches the saturation oint and replacing the medium withdrawn by a fresh supply thereof.

4. In the art of drying rubber, the steps of vertically supporting sheets of rubber in spaced relation in an enclosed chamber, circulating a heating gaseous drying medium downwardly in the chamber between the sheets, withdrawing the medium from the chamber and returning it again, reheating the medium to replace the heat lost by evaporation of the moisture in the rubber and removing from the body of the substantially saturated medium a portion thereof and replacing the portion withdrawn by a fresh supply.

5. In the art of drying rubber, subjecting the rubber to the action of a rapidly circulating drying medium, which is maintained at a constant high temperature and a constant state of substantial saturation, by re heating the medium during the entire operation to replace the heat lost by evaporation and withdrawing a portion of the medium as it reaches the saturation point and replacing the medium withdrawn by a separately preheated fresh supply thereof.

6. In the art of drying rubber, subjecting the rubber to the action of a drying medium by circulating the medium about the rubber and maintaining it at a constant high temperature and a constant state of substantial saturation from the moisture in the rubber, by reheating the medium during the operation to replace the heat lost by evaporation and by withdrawing a portion of the medium as it reaches the saturation point and replacing the medium withdrawn by a fresh supply preheated substantially to said constant temperature.

7. An apparatus for drying rubber comprising a chamber, means for supporting sheets of rubber in vertical spaced relation in the chamber, a flue connected with the chamber at separated points, means for withdrawing gas from the chamber through the flue to return it to the chamber, said flue being so arranged as to direct the flow of gas between the sheets.

8. An apparatus for drying rubber comprising a chamber, means for supporting sheets of rubber in vertical spaced relation in the chamber, a flue connected with the chamber at separated points, means for withdrawing gas from the chamber through the flue to return it to the chamber, heating means Within the flue, said flue being so arranged as to direct the flow of gas between the sheets.

9. An apparatus for drying rubber comprising a chamber, means for supporting sheets of rubber in Vertical spaced relation in the chamber, a flue connected with the chamber at separated points, means for withdrawing gas from the chamber through the flue to return it to the chamber, a heater in the flue, said flue and said last-named means being so arranged as to direct the flow of gas downwardly between the sheets.

10. An apparatus for drying rubber comprising a chamber for the reception of the rubber, a plurality of by-passes around the chamber, means for withdrawing the gas from the chamber by the by-passes and returning it to the chamber, flues for withdrawing a portion of the gas from the chamber, and means for directing fresh preheated gas directly into the chamber 11. An apparatus for drying rubber com prising a chamber for the reception of the rubber, a flue connected with the interior of the chamber at separated points, means for withdrawing gas from the chamber through the flue to return it to the chamber, means for withdrawing a portion of the gas entirely from the chamber and means adjacent the entrance for the gas from the flue into the chamber for admitting a fresh supply of gas.

12. Apparatus for drying rubber comprising a chamber for the reception of the rubber, means whereby the rubber may be supported therein so as to provide a plurality of vertical passageways between the rubber, a flue connected with the interior of the chamber at separated points, means for with drawing gas from the chamber through the flue to return it to\ the chamber, a heater within the flue, said flue being arranged to direct the gas through the vertical passageways, means for Withdrawing a portion of the gas from the system, and means for admitting separately preheated gas to the chamber adjacent the entrance from the flue to the chamber of the I'e-heated gas.

13. Apparatus for drying rubber comprising a chamber, a flue in communication with said chamber at separated points, a gas impeller for withdrawing gas from the chamber and through the flue, said impeller being located at the entrance of the gas from the fine into the chamber, means for entirely withdrawing a portion of the gas from the chamber and means for directing fresh gas into the chamber adjacent said entrance.

WILLIAM r. RUNALS, JR. 

